Hi, I had a hard drive failure and am using Fedora 17 64-bit the same Nvidia hardware. the Garbling is slightly lesser although the problem exists. I think, after an hour of use or so, this issue increases?

[adminguy@localhost ~]$ CLUTTER_PAINT=disable-clipped-redraws:disable-culling /bin/gnome-shell --replace
JS LOG: GNOME Shell started at Fri Jun 01 2012 18:55:55 GMT+0530 (IST)
Window manager warning: Log level 16: STACK_OP_REMOVE: window 0x1ab not in stack
(gnome-shell:1952): folks-WARNING **: Failed to find primary PersonaStore with type ID 'eds' and ID 'system'.
Individuals will not be linked properly and creating new links between Personas will not work.
The configured primary PersonaStore's backend may not be installed. If you are unsure, check with your distribution.
Window manager warning: Got a request to focus 0x200008c (Bug 720605) with a timestamp of 0. This shouldn't happen!

and I tried scrolling through web pages which are images heavy. the problem is not showing up after running above command. I will update if the problem reappears.

Interestingly, I never faced the issue with Terminal(gnome-terminal) as many reports. For Me, Firefox,Image viewers like shotwell,eog shows image garbled or "stuck at middle" while scrolling. it is a lot lesser in Fedora than Debian possibly because it is using Gnome-Shell-3.4.